Thermal circuit-closer



. R. L. MCELROY. THERMAL CIRCUIT CLOSER. APPLlcATloN FILED FEB. 19. 1918. 1,374,596. Patented API*- 12,1921.

2 SHEETS-SHEET l.

Wilke/Sjef@ R. L. MCELROY. THERMAL CIRCUIT CLOSER. APPLICATION FILED FEE, 19, 1918.

1,874,596. Patented Apr. 12, 1921.

2 SHEETS-SHEET 2.

Witnesses n Inventor.-

Hoeri C ro IWI/m7 By his Any,

`UNITED STATES ROBERT L. MCELROY, OF YORK, lN'. Y.

PATENT OFFICE.

THERMAL CIRCUIT-CLOSER.

speci'cation of Letters Patent. Patented Apr. 12, 1921.

Appneation med rebruaryile, 191s. seriali No. 218,137,

To all whom t may concern:

Be it known that I, ROBERT L. MoELRoY, a citizen of the United States, residing in New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Thermal Circuit-Closers, of which the following is a s ecification.

y invention relates to lire alarm control systems of the general and 'broad class, wherein arise of temperature at a predetermined rate by reason of lire, automati- .cally puts into operation signaling mech-aof. its particular series; and the entire series,

supplied at some convenientv central point with a multiple annunciator with an indicator for each and every apparatus in the entire plant; and an audible signal such as a bell is put into actuation simultaneously with the actuation of any annunciator so as to indicate that a fire is occurring at some point in the system, as is indicated by the annunciator'.

In the apparatus shown, the thermostat comprises a pipe'or pipes composed of ne b'ored wire like copper, or other similar highly conductive tubing, usually arranged in the rooms or apartments to be protected adjacent to the ceiling in substantially the form of a rectangle; each room being provided outside of the same with an individual annunciator connected with the thermally controlled air-actuated SignaLactuating device, which comprises an'air chamber in connection with the thermostatic tube or circuit, closed by two flexible diaphragms of dif-v ferent diameters, or different degrees of flexibility, which .upon sudden increase of the air pressure, in the tubing,4 are by the consequent flexing by the increased air pressure, adapted to set into operation electric mechanism actuating the several annunciatorsland setting into operation the audible s1 a ysaid inventionis shown, described and claimed 1n the following specification of whlch the accompanying drawing forms a part, wherein similar letters or numerals of reference designate like or equivalent parts wherever found throughout the several vlews; and in which Figure l is a diagrammatic top-plan view, o f one of the contact making and breaking slgnal actuating elements of such device looking from the top, connected up with its a1r .thermostatic piping, an annunciator and the audible signal bell mechanism, one modilied form of arrangement, of the thermotatic air-.piping being shown in dotted mes;

Fig. 2 is a side view in central vertical section of the electric circuit making and breaking device looking from the bottom of Fig. 1, in the direction of the arrow,

taken Aon substantially the line 2-2 of Fig. l;

Fig. 3 is a side view in detail of a portion of the mechanism shown in Fig. 2,

the several electric make and break mechanisms; C,the audible signal (in this case a spring-.motor actuated alarm bell); D2, the main central annunciator connected up with each of the make and break mechaf nisms B; and-D', (Fig. 4), the individual 'looking toward the left thereof, the top annunciators outside of each room` orA section connected with an individual make and break apparatus B.

The thermostatic make and break mechanism of my improved lire-*alarm signaling device, in the particular form and embodiment thereof, which I prefertoy use, but to the exact construction of which I do not intend to limit myself, comprises a supporting base member 11, adapted -tobe Vsecured in position either uy on the side-wall or ceiling Of the room 1D. which the same is to be situated, (usually upon the ceiling), by screws, or in any other desired manner. Such base-plate is .formed ofr any suitable material but isl usually of bronze or brass, and of the form shown in Fig. 2, being vin the form of a supporting-base portion 13, having on opposite sides the upwardly extending standards 14 and 14', between which is located the air-chamber central standard member 15 formed integral with the baseplate 13, having an air inlet duct' 16, in communication at the bottom, with an air-inlet duct 17, in air-tight lcommunication with the air thermostatic pipe member A, at either end thereof, such duct 17 preferably extending fully across the base-plate 13. The vertical duct 16 communicates at the top at the point 18 (F ig. 2)., with the airchamber 19, which chamber 1s in communication by way of an air duct 20, with the smaller air-chamber 21 on the opposite side of such standard 15.

Each of the air-chambers 19 and 21, are preferably cylindrical in form and each provided with a' female screw-thread in their 'interior annular peripheral walls in which is tightly screwed, an annular malethreaded-bushing or diaphragm-ring 22, in the case of the chamber 19; and the like annular-bushing or diaphragm-ring 23 in the case of the air-chamber 21.

F irmly secured at its peripheral edge in the bushing or diaphragm-ring 22, is a -resilient flexible-diaphra m 24, such pe-` ripheral connection wit the bushing-ring being made an air-tight ioint, by cementa'- .tion or other method, so that when the ring 22 is screwed fully home, the air-chamber 19 is out of communication with the atmosphere, savefby way ofthe relief of the ther mostatic vair tubin A', as hereinafter described. And the llke bushing or ring 23 is provided with a similar flexible diaphragm 25, secured in place in the same manner which hermetically seals the air-chamber 21 at its puter face. Securely held in position in each of the standards 14 and' 14',

adjacent to the tops thereof, usually by be-` Y ing. inclosed in metallic bushings 26 and 26', screwed into such standards 14 and 14', are insulating plugs or bushings of rubber or other like electric insulating'material 27 and 27', provided with female screw-threads through which the adjustable electric contact screws 28 and 28 pass, being turned by the milled thumb-heads 37 and 37', re-

spectively.

flhe diaphragms 24 and 25 are of anyv sultable fiexible material im ervious to' air, such as .thin steel, bronze, m1ca,etc., but for sensitivity.. preferably mica, and are each provlded, preferably at the centeryvvith contact-pms 30, extending outwardly therefrom, usually in the form of headed-studs, passing outward through the diaphragm keeping the pawl-tooth 62 in locking vibratorily supported upon a pivot-pm 33,

an inverted U-shaped yoke-lever 34, the downwardly depending ends'of which are in contact with the outer ends of the studs 30, of the diaphragms 24 and 25, on their respective sides, the ends of such yoke-lever being usually provided with platinum or other like contact plates 35, adapted to contact with the point 36 of their respective electric contact-screws 28 and 28.

The contact screw 28 is in electrical connection by way of an electric conducting Wire 40, with a spring contact-piece 41, secured to the base-plate 13, by a screw, as shown in Fig. 2, which contact-piece 4l is of spring resilient metal, and when the parts are in position, is in electrical contactwith a spring contact-member 43, secured to the dome or cover piece 44, which is secured to the base-plate 13.by screws 46. Fig. '1 lor in any other desired manner; and the spring contact members 41- and 43 are insulated from the 'base-plate, ,and from the dome 44 (which like the base-plate is usually of brass) respectively, by insulating plates 43'. Held in place in suitable sockets either in the base flange of the dome 44 as shown, or in the base-platel 13, or `in both on either side, in line with andl adjacent to the standards 14 and 14', are insulating thimbles 47 and 47', through which pass the plus and minus Wires of the electric actuating circuit, energized bythe battery or other source of electrical supply E Fig. 1.' The minus wire M, being connected with thespring-contact 43 by a .wire 50, `and the plus wire P being directly connected with the contact-screw 28 by a wire 51.

Passing through a hard rubber or other suitable insulating bushing 48, (similar to and held in place as are the thimbles or bushings 47 and 47'), is a branch minus wire 53, in electrical conductive relation by way of a wire 53', vwith the inverted .U- shaped yoke-lever 34. The contact 43 is connected up with the battery or source of electrical energy E, through a minus wire 56', byway of an electro-magnet 56, connected with the plus wire 57; which electro-magnet normally holds a pawl-lever 58, rocking on the pivot 59 against the tension ofthe coil spring 60, by its action on the armature 61, secured to such lever 58, thus and retaining position` with the teeth 63 of the ratchet-wheel 63,v which are also in actuating contact with the cam 64, of the bellhammer lever 65; which rachet-wheel 63 forth against the bells 67, as to give anl audible signal. y

In devices of this character, it is essential in most cases that the device should be adjustable within wide thermal limits; and

i also that slight and slow' changes of the surrounding air-chamber temperature should not affect the apparatus so as tol throw the same into actuation; and to suchv ends, it will be seen that the pipe system generally denoted by A, is in connection with the large chamber 19 and also indirectly with the chamber 21, through the very constricted passage 20. This last named passage 20 prevents the quick passage of air from the larger chamber to the smaller when there is a sudden rise intemperature, thereby causing more pressure against the larger diaphragm so that the larger diaphragm overcomes the force exerted by the smaller and causes the yoke member to make contact with the screw 28 and break contact with the screw 28. On the otherhand, the passage 20 acts as a balancing or compensating duct when slow rises in temperature are in action, wherein during such slow rises the expansion of the air within the pipes system A is comparatively slow, and inasmuch as the restricted passage 20 is sufficiently large to permit the balancing of the pre-ssures in the chamber 10 into the chamber 21 by flowing through the restricted passage 20?, it is obvious that the twq diaphragms remain in their normal balance to each other and without any tendency to operate until the pressure in them becomes great, when the fact that the larger diaphragm because of its size exerts more force on the yoke member, will cause the larger to overcome the smaller and again operate .the yoke member to make contact with the screw 28 and break contact with the screw 28.

It will also be seen that since the signal device is operated by the breaking of the contact with the screw 28 the device will also be operated whenever through any kind of accident the circuit including the signal device is broken. This insures that the signal device can never fail to operate through a breaking of the circuit or failure of the electric source. Consequently when any sudden change in temperature occurs to increase the expansion in any part of the pipe system A, such as may be caused by a lire, this expansion will first be communicated to the chamber 19, and actuate the diaphragm 24 before the expansion can be 25.` Secondly, the diaphragm 24 is about four times the area of the diaphragm 25 so that when any such sudden change in tem- .perature occurs, the pressure exercised thereon will be equally greater than on the diaphragm 25 to facilitate the recording of such sudden change in temperature.

In the present system it makes no diHerence in the elicient operation thereof whether the fluid pipe system A is entirely closed, partially closed, or fully open to the atmospheric pressure, such as is indicated by the pipe system indicated by dotted lines A', wherein in the terminal ends thereof one of the ends 81, is shown closed or plugged and the other end 80, thereof is shown open to atmosphere. This is also fully set forth in Fig. 4 wherein the pipe system A is shown as being affected within the zones L, R, and T, and in which Zones for instance the pipe may either be crushed flat, cut through, or otherwise distorted from normal condition, but such condition would not affect the proper operativeness of the control members between which such pipe system was abnormal. lVhile, in ordinary lpractice, I prefer to have the pipe system arranged as a closed circuit, still there are conditions where it is preferable to havevthe system either partially or fully open to atmosphere, as the proper operation of the device as a signaling mechanism is not interfered with in any way by such alternate pipe system.

It is preferable, in order to have the apparatus extremely sensitive to quick and sudden rises in temperature, that the contact device should be adjusted, seasonably, at least twice a year; that is, in the spring out for summer temperature, and in the autumn in for winter temperature; and this is done by manipulation 0f the contact-screw 28', after removal. of the dome 44, by turning the same in or out, the screw being provided with an index-disk 70, provided with a suitable peripheral thermal degree scale, above which secured to the standard 14 is'the stationary thermal degree. indicating hand 7 0.

It will be seen upon examination of llig. 2, that the diaphragm 25 is considerably smaller than is the diaphragm 24, being, as shown in the drawing, but practically onehalf the diameter of 24, whereby whatever the air pressure in the air-chambers 19 and 21, coming from the pipes A or A', by way of 17, 16, 18 and 2() that the superficial pressure exerted upon 24, will be substantially four times that exerted upon 25; and the adjusting screws 28 and 28 having been adjusted into the position shown in Fig. 2, so that the circuit through the screw 28 and the yoke 34 is closed while the circuit through the like screw 28 and the opposite side of said yoke is normally open, the device is ready for thermal actuation. lf. now by reason of lire, there should come a sudden increase of pressure in the pipes A and A', and consequently in the air-chambers 19 and 21, it is evident that the dierence in the superficial pressure exerted upon 24, by reason of its larger area, over that exerted upon the smaller diaphragm 25, will cause the diaphragm 24 to be flexed outward, while its greater power causes the diaphragm 25 to be flexed inward, so as to break the contact with 28, and thus breaking the circuit throu h the electro-magnet 56, which will release t e pawl-lever 58, thus releasing the ratchet-wheel 63, so as to cause actuation of the bell-tongue lever 65, so as to ring the bell 67, while at the same time the opposite side of the yoke 34, making contact with the. electric adjusting screw 28', will close the annunciator circuit.

It will be seen that in its fundamentals, this fire-alarm system is based upon an electric make and break mechanism, thermally actuated upon a rise in temperature, which is in connection with, and at all times sealed into, a small bored air-pipe or duct of suitable length, formed of high heat conductive metal or other suitable material, located in the apartment or apartments to be protected against lire, one side of such make and break electric mechanism being in constant closed electric circuit, with a normally inoperative fire-alarm (in this case an audible signal in the form of a bell actuated by a spring-motor), while the other side is normally in open electric-circuit with a visual multiple fire zone indicator annunciator system. 1t will also be seen that should a sudden rise in temperature take place at any part of the circuit included in the airduct piping, caused by re, say a rise of 5 to 7 degrees, the quick expansion of the air within the tube-duct Asystem will cause the inverted `U-shaped yoke-member 34, of that particular making and breaking mechanism B nearest to the lire-zone to be immediately actuated, and to swing from the closed circuit position at the left of Figs. 1 and 2, (thus breaking such normally closed circuit), to the open circuit or rightside, so as to cause the yoke-member to close the normally open annunciator circuit, thereby causing the {ire-alarm bell 67 to ring and the proper annunciator indicating the particular apartment, or the situation ct' the make-and-break mechanism B to be put into operation.

1n this system, the device just described is installed in various places, on each floor or in rooms, in the building, and they are all connected together as hereinbefore described with a fine wire-like tube of copper or other suitable metal 0r material. The electric-Ciraar/aces cuit making and breaking devices B, (each setting into operation Jsimultaneously th'e audible signal and their individual annunciator signals), being located at predetermined spacings of the tubing, the 'ends of which tubing may, according to circumstances, be left opened, closed, connected together, or one end opened and one end ing and wiring, etc., and in such F ig. 4, I

have shown four electric-circuit making and breaking devices B, connected up by a closed air-duct pipe circuit composed of A,l such circuit trapping the airY therein, except for an air-vent suiiicient to allow for slow rises and falls in temperature, which vent may be located at any required point, say 82. These making and breaking circuit devices B, as shown in Fig. 4, merely for purposes of description and convenience, are numbered from 1 to 4, inclusive; and located adjacent to each of the same and preferably outside of the room containing the same, and usually in `a common corridor, (not shown) are annunciators D', having the same number of annunciating visual signal traps or other visual signaling devices as there are 4), each of which annunciators is included in an electrical circuit or circuits with all the make-and-break mechanisms B, in such manner that upon the thermal actuation of any one of said mechanisms, the audible signal or bell 67 and the particular annunciator signal bearing the same number as the particular mechanism B operated, of all the several annunciators, will beactuated and thrown into visual position. Say for instance, should a ire occur at the point marked L,at` the right of Fig. 4, this will actuate first the electric circuit making and breaking mechanism B, numbered 4, and will at the same time, throw intov visuality the number 4 at each of the several visual annunciators D and at the same time actuate the audible signal bell 67. If however,

`the fire should occur at the point marked R,

the point marked T, this will cause the simultaneous actuation of the mechanisms B3 and B4. And it will be seen that should any one of these mechanisms fail to act, that the continued expansion of the air in the tubing A, will in a short period of time, cause actuation of other immediately adjacent mechanisms B until all are put into operation, whereby a lire Aindicating and alarm signal system is provided which is practically impossible to in any manner be put out of commission, so as not to signal the fire-alarm, both visually and audibly,

shortly after the starting of a fire.

In Fig. 4, D2 indicates a multiple annunciator showing all the several apartments or ioors, this is shown in visual position, like the individual annunciators D', indicating ire adjacent to mechanisms B3 and B4,

It is evident that many changes in the construction, combination, and arrangement of the several parts of this apparatus, may be made Without departing from the spirit of this invention, or exceeding the 'scope of the claims and it is not intended to limit the same to the exact structures, combinations, or methods of arrangement shown.

I claim:

l. In an apparatus of the class described, the combination of a pair of sensitive means dilierently susceptible to pressure; and a movable means unequally and oppositely iniiuenced by said sensitive means to open one circuit and close another.

2. In an apparatus of the class described, the combination of a pair of chambers connected by a restricted passage; a sensitive means associated with each chamber and differently susceptible to pressure therein; anda movable operating means oppositely influenced by said sensitive means.

3. In an apparatus of the class described, the combination of a pair of chambers connected by a very restricted passage; sensitive means associated with the chambers respectively and differently susceptible to pressure therein; a movable operating means unequally and oppositely influenced by said sensitive means; and a fluid pres.

sure container communicating `With the chamber associated with the sensitive means exerting the greatest influence.

4. In an apparatus of the class described, the combination of a pair of chambers connected by a very restricted passage; sensitive means forming part of the Wall of the chambers respectively and diii'erently susceptible to pressure; a movable means unequally influenced to move in opposite directions by said sensitive means to open one circuit and close another; and a fluid pressure container communicating with the chamber associated with the sensitive means exerting the greatest influence.

5. In an apparatus of the class described,

-a large air chamber connected byv a restricted opening; a fluid pressure pipe communicating With the large air chamber; small' and large flexible diaphragms forming the one Wall of the air chambers respectively;

and a ulcrumed operating member pressed in opposite directions by said diaphragms respectively and thereby adapted to rock the member by the differential pressures of the diaphragms'.

7 In an apparatus of the class described,

the combination of a support having a small air -chamber and a large air chamber arranged on opposite sides thereof and connected by a very restricted opening; a Huid pressure pipe communicating with the large air chamber; small and large flexible diaphragms forming the outer Wall of the air chambers respectively; and an intermediately fulcrumed U-shaped contact yoke member having its arms pressed 'outwardly by said diaphragms respectively and thereby adapted to rock the yoke member by the differential action of the diaphragms.

8. In an apparatus of the class described, the combination of a main standard having a small air chamber and a large airy chamber arranged on opposite sides of the standard and connected by a restricted opening; a closed Huid pressure pipe communicating With the large air chamber; flexible diaphragms forming the outer Wall of the air chambers respectively; and an inverted U- shaped contact yoke member fulcrumed at the upper part of said main standard and having its arms pressed by` said diaphragms respectively and thereby. adapted to `be moved in and out to rock the U-shaped con-I tact yoke member by the differential action of the diaphragms.

9. In an apparatus of the class described,

' the -combination of a main standard; a sensiother on the rocking of said member by y the sensitive means.

10. In an apparatus of the class described, the combination of a base plate; a main lstandard thereon having air chambers ar.

ranged thereon; a Huid pressure pipe communicating with the air chambers; diaphragms forming one wall of the air chambers respectively; supporting standards extending upward from the base-plate; insulated electric-contact screws --adjustably mounted in the supporting standard; and a contact yoke member ulcrumed on the main standard and having its arms pressed by said diaphragms respectively and' ythereby ladapted tobe brought into and out of contact with said contact-screws respectively upon the rocking of the yoke member by the action ofthe diaphragms.

11. In an a paratus of the class described,l the combination of a base plate; a main standard thereon having a small air chamber and a large air chamber arranged on opposite sides of the standard and connected by a restricted opening; a closed iuid pressure contact with said contact-screws respectivelyy upon the rocking of. the U-shaped contact yoke member by the differential pressure action of the diaphragms.

12. In a device of the class described, a

4 supporting base-plate; a central hollow standard forming a pair of air-chambers; two ilexible diaphragms forming portions of the walls of the air-chambers, one of said diaphragms being of larger area than the other; an adjustable electric contact-piece adjacent to the exterior of each diaphragm; a movably mounted circuit-makingI 4and breaking member adapted to close one circuit when moved in one direction and to break such circuit and close the other when -moved in the other direction; the lcircuit -making and breaking member being moved from one position to theother by the Hexation of thediaphragms caused by variations in the pressure of the entrapped air.

13. Ina device of the class described, a supporting base-plate; la central hollow standard forming a pair of air-chambers; two flexible diaphragms forming portions of the flexing outward of the larger diaphragm and the consequent inward flexing of the smaller diaphragm. 'y

14. In a device of the class described, a base-plate; a central standard having a pair of air-chambers supported by the base-plate; two flexible diaphragms walling the air chambers on oppositesides; standards extending upward from the base-plate adjacent to the diaphragms; insulated electric contact-screws adjustably mounted in the side standards adapted to be moved toward and away Jfrom the diaphragms; an inverted U-shaped contact member, the arms of which are adapted to be brought into and out ofcontact with the contact-screws on either side upon the rocking of the U-shaped contact yoke-member; and means pivotally connecting the yoke-member with the central standard in such manner that upon theV flexing of the diaphragms one circuit will be broken and the other closed by the contact of one of the other arms thereof with the contact screw.

15. In a device of the class described, a base-plate; a central standard having a pair of air-chambers supported by the base-plate; two flexible diaphragms of different diameters walling the lair-chamber on opposite sides; standards extending upward from the base-plate adjacent to the diaphragms; insulated electric contact-screws adjustably mounted in the side standards adapted to be moved towardl` and away from the diaphragms; an inverted U-shaped contact yoke-member, the arms of which are adapted to be brought into and out of contact with the contact-screws on either. side upon the rocking of the U-shaped vcontact yoke-member; and means pivotally connecting the yoke-member with the central standard in such manner that upon the'exing of the diaphragms one circuit will be broken and the other closed by the contact of one of the other arms thereof with the contact screw. ROBERT L. MGELROY.

Witnesses:n

JAMES G, NOLEN, H. M. KILPATRICK. 

